[repl] should not wait a result when debug on device
[repl] should not wait a result when debug on device

If run following for debugging on device,
it will wait a result of STDOUT until terminating a debugger.
And then, anything (debugger prompt, inputted a command) would not be displayed on terminal.

```
remote_arch = `#{cmd}`.strip
```

katsuyoshi/RubyMotion,hboon/RubyMotion,hboon/RubyMotion,HipByte/RubyMotion,katsuyoshi/RubyMotion,katsuyoshi/RubyMotion,katsuyoshi/RubyMotion,HipByte/RubyMotion,HipByte/RubyMotion,hboon/RubyMotion